From c7dcb6c9aa85fa310251dad7e233eb955a5235ed Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Mon, 5 Feb 2024 16:40:08 -0800 Subject: selftests/bpf: mark dynptr kfuncs __weak to make them optional on old kernels Mark dynptr kfuncs as __weak to allow verifier_global_subprogs/arg_ctx_{perf,kprobe,raw_tp} subtests to be loadable on old kernels. Because bpf_dynptr_from_xdp() kfunc is used from arg_tag_dynptr BPF program in progs/verifier_global_subprogs.c *and* is not marked as __weak, loading any subtest from verifier_global_subprogs fails on old kernels that don't have bpf_dynptr_from_xdp() kfunc defined. Even if arg_tag_dynptr program itself is not loaded, libbpf bails out on non-weak reference to bpf_dynptr_from_xdp (that can't be resolved), which shared across all programs in progs/verifier_global_subprogs.c. So mark all dynptr-related kfuncs as __weak to unblock libbpf CI ([0]). In the upcoming "kfunc in vmlinux.h" work we should make sure that kfuncs are always declared __weak as well. [0] https://github.com/libbpf/libbpf/actions/runs/7792673215/job/21251250831?pr=776#step:4:7961 Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/r/20240206004008.1541513-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov --- tools/testing/selftests/bpf/bpf_kfuncs.h | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) (limited to 'tools/testing/selftests/bpf') diff --git a/tools/testing/selftests/bpf/bpf_kfuncs.h b/tools/testing/selftests/bpf/bpf_kfuncs.h index 0cd4111f954c..14ebe7d9e1a3 100644 --- a/tools/testing/selftests/bpf/bpf_kfuncs.h +++ b/tools/testing/selftests/bpf/bpf_kfuncs.h @@ -9,7 +9,7 @@ struct bpf_sock_addr_kern; * Error code */ extern int bpf_dynptr_from_skb(struct __sk_buff *skb, __u64 flags, - struct bpf_dynptr *ptr__uninit) __ksym; + struct bpf_dynptr *ptr__uninit) __ksym __weak; /* Description * Initializes an xdp-type dynptr @@ -17,7 +17,7 @@ extern int bpf_dynptr_from_skb(struct __sk_buff *skb, __u64 flags, * Error code */ extern int bpf_dynptr_from_xdp(struct xdp_md *xdp, __u64 flags, - struct bpf_dynptr *ptr__uninit) __ksym; + struct bpf_dynptr *ptr__uninit) __ksym __weak; /* Description * Obtain a read-only pointer to the dynptr's data @@ -26,7 +26,7 @@ extern int bpf_dynptr_from_xdp(struct xdp_md *xdp, __u64 flags, * buffer if unable to obtain a direct pointer */ extern void *bpf_dynptr_slice(const struct bpf_dynptr *ptr, __u32 offset, - void *buffer, __u32 buffer__szk) __ksym; + void *buffer, __u32 buffer__szk) __ksym __weak; /* Description * Obtain a read-write pointer to the dynptr's data @@ -35,13 +35,13 @@ extern void *bpf_dynptr_slice(const struct bpf_dynptr *ptr, __u32 offset, * buffer if unable to obtain a direct pointer */ extern void *bpf_dynptr_slice_rdwr(const struct bpf_dynptr *ptr, __u32 offset, - void *buffer, __u32 buffer__szk) __ksym; + void *buffer, __u32 buffer__szk) __ksym __weak; -extern int bpf_dynptr_adjust(const struct bpf_dynptr *ptr, __u32 start, __u32 end) __ksym; -extern bool bpf_dynptr_is_null(const struct bpf_dynptr *ptr) __ksym; -extern bool bpf_dynptr_is_rdonly(const struct bpf_dynptr *ptr) __ksym; -extern __u32 bpf_dynptr_size(const struct bpf_dynptr *ptr) __ksym; -extern int bpf_dynptr_clone(const struct bpf_dynptr *ptr, struct bpf_dynptr *clone__init) __ksym; +extern int bpf_dynptr_adjust(const struct bpf_dynptr *ptr, __u32 start, __u32 end) __ksym __weak; +extern bool bpf_dynptr_is_null(const struct bpf_dynptr *ptr) __ksym __weak; +extern bool bpf_dynptr_is_rdonly(const struct bpf_dynptr *ptr) __ksym __weak; +extern __u32 bpf_dynptr_size(const struct bpf_dynptr *ptr) __ksym __weak; +extern int bpf_dynptr_clone(const struct bpf_dynptr *ptr, struct bpf_dynptr *clone__init) __ksym __weak; /* Description * Modify the address of a AF_UNIX sockaddr. -- cgit v1.2.3